Slide door-carrying cab

ABSTRACT

A slide door-carrying cab is provided which includes a slide door capable of forming a sufficient clearance between a rear portion of the cab and a back of an operator&#39;s seat, reclining the back at a sufficient angle, and giving an excellent comfortableness to an operator. The cab is provided in the position on a turntable which is offset from the center of a swinging movement thereof. An outer side portion of the cab has an outwardly bulging surface, and the slide door which moves along the curved surface is provided at a front section of the outer side portion. A rear portion of the cab is made of outwardly bulging two-dimensionally bent rear curved glass, and an outer edge of the rear portion is made to stay within a turning radius of an outer edge portion of the turntable.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a slide door-carrying cab forconstruction machines.

[0003] 2. Description of the Related Art

[0004] The known slide door-carrying cabs for construction machinesinclude the cab for construction machines disclosed in, for example,Japanese patent publication (JP-A-2001-49696), pages 3 to 4, FIGS. 2 and7. According to this patent publication, a turntable is provided on atraveling gear which is at a lower portion of a construction machine,and a cab in the position on the turntable which is offset from thecenter of a swinging movement thereof. The cab is formed so that anouter side portion thereof bulges outward curvilinearly. The outer sideportion of the cab is provided with a slide door, and a radius ofcurvature of a rear half section of the outer side portion is setsmaller than that of a front half section thereof. Consideration isgiven to the slide door so that an orbit of an outer edge portion of theslide door in opening and closing movements thereof stays within aturning radius of an outer edge portion of the turntable.

[0005] FIG. 3 is a perspective view of the cab disclosed in this patentpublication. The construction of the cab will be described in detail onthe basis of what is shown in FIG. 3. The cab 20 is provided with afront portion 21, a top plate portion 22, an inner side portion 23, arear portion 24, and an outer side portion 25 having a slide door 30 ina front half section 27 thereof and a wall surface portion in a rearhalf section 26 thereof. The slide door 30 is slidingly moved with theslide door 30 guided by an intermediate guide rail 31, an upper guiderail 32 and a lower guide rail 33 which are provided on the outer sideportion 25. The outer side portion 25 is formed so as to have anoutwardly bulging curvilinear surface, and the radius of curvature ofthe rear half section 26 of the same portion 25 is set smaller than thatof the front half section 27 thereof, i.e. the slide door 30. The frontportion 21 is provided with front glass 21a, the inner side portion 23flat side glass 23a, the rear portion 24 flat rear glass 24a, and therear half section 26 of the outer side portion 25 two-dimensional curvedglass 26a respectively.

[0006] This patent publication says that, when the slide door 30 isopened, the lateral size of a rear half portion of the cab 20 can bewidened owing to the above-described structure to as great an extent aspossible without causing a rear end portion of the slide door 30 toproject to the outside of the turning radius of a swinging movement ofan outer edge of the turntable, and that an effective space in the cabcan thereby be enlarged limitlessly.

[0007] FIG. 4 is a side view of a rear-end small-turn type power shovel1, an example of a construction machine on which the cab disclosed inthe above patent publication is mounted. A turntable 3 swingably mountedon a traveling gear 2 is mounted with the cab 20. A front end portion ofthe turntable 3 is mounted a working machine 4. According to what isshown in FIG. 7 in this patent publication, a rear portion of the cab 20is made of a flat vertical wall.

[0008] FIG. 5 is a sectioned side view of a mode of embodiment to whichan operator's seat 40 is added of the cab 20 disclosed in the abovepatent publication, and FIG. 6 a plan view of the same embodiment.Referring to FIGS. 5 and 6, the cab 20 is fixed in the position on theturntable 3 which is offset from the center C of a swinging movementthereof 3, and an outer edge 8 (a broken line shows a turning circle ofthe slide door 30 being opened) of a turning circle of the slide door 30being opened and closed stays within a turning radius R of the outeredge of the turntable 3. The cab 20 is provided with a total of fivesupport posts 34a, 34b, 34c, 34d, 34e in the four left and right cornersthereof and at an intermediate section of the portion thereof which ison the side of the slide door 30. In the interior of the cab 20, anoperator's seat 40 having a back 41 against which the back of anoperator can be reclined is provided.

[0009] In this structure, flat vertical rear glass 24a is provided inthe rear portion 24 of the cab 30, so that a clearance M between theback 41 of the operator's seat 40 and the rear glass 24a is narrow. Theclearance M is really too narrow to place, for example, a tool boxtherein, and proves inconvenient. Moreover, in order to recline the back41, a reclining angle β cannot be set large, and an operator thereforecannot take a break in a comfortable posture during a rest period.

SUMMARY OF THE INVENTION

[0010] The present invention has been made with the inventor's attentionpaid to these problems, and aims at providing a slide door-carrying cabcapable of having an outer side portion of the cab stay within a turningradius of an outer side portion of a turntable, and securing asufficient space between a rear portion of the cab and a back of anoperator's seat, and very comfortable for an operator to work and resttherein.

[0011] To achieve this object, the present invention provides a slidedoor-carrying cab for construction machines, including an outer sideportion provided in the position on a turntable mounted swingably on atraveling gear which is offset from the center of a swinging movementthereof, an outer side portion formed on an outer circumferential sideof the turntable so that the outer side portion extends so as to have anoutwardly bulging curvilinear surface, and a slide door provided in theouter side portion, opened and closed slidingly along the curvilinearsurface, and having an orbit of opening and closing movements thereof anouter edge of which is adapted to stay within the turning radius of anouter edge portion of the turntable. A rear side portion of the cab ismade of rear curved glass staying within a turning radius of the outeredge of the turntable and having an outwardly bulging curved surface.

[0012] According to the present invention, the rear side portion of thecab stays within the turning radius of the outer edge portion of theturntable, and is made of rear glass having an outwardly bulging curvedsurface. Therefore, there is not a fear of causing the cab to contact anoutside obstacle when the turntable is swung. Moreover, a clearancebetween the back of the operator's seat and the rear side portion of thecab can be enlarged, so that it becomes possible to secure astoreroom-forming space sufficiently, increase, the seat back recliningangle, and thereby improve the operator's comfort in the cab when heworks and rests in the cab. Since the cab has curved surfaces, theexternal appearance thereof becomes excellent.

[0013] According to the present invention, the radius of curvature ofthe rear curved glass may be set equal to that of the side curved glassprovided at the rear section of the curved surface-carrying outer sideportion. In this structure, the same mold can be used when the sidecurved glass and rear curved glass are molded, so that the cost can bereduced to a lower level.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] A preferred embodiment of the present invention will now bedescribed with reference to the accompanying drawings, wherein:

[0015]FIG. 1 is a sectioned side view of the cab according to thepresent invention;

[0016]FIG. 2 is a sectioned plan view of the cab according to thepresent invention;

[0017]FIG. 3 is a perspective view showing the external appearance of arelated art cab;

[0018]FIG. 4 is a side view of a power shovel on which such a cab as isshown in FIG. 3 is mounted;

[0019]FIG. 5 is a sectioned side view of the related art cab; and

[0020]FIG. 6 is a sectioned plan view of the cab of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0021] A mode of embodiment of the slide door-carrying cab according tothe present invention will be described in detail with reference to thedrawings. The statement about the cab will be given with such a powershovel as is shown in FIG. 4 taken as an example of a machine to whichthe present invention is applied.

[0022] Referring to FIG. 1 and FIG. 2, a cab 10 is provided in theposition on a turntable 3 which is offset from the center C of aswinging movement thereof. An outer side portion 11 constituting a sidewall surface of the cab 10 is made so as to have an outwardly bulgingcurved surface. A slide door 12 opened and closed as the door is movedslidingly along the curved surface is provided at a front section of theouter side portion 11, and a rear wall surface portion at a rear sectionof the same. An outer edge (a broken line shows the slide door 12 in anopened state) of an orbit of opening and closing movements of the slidedoor 12 is adapted to stay on the inner side of a turning radius R of anouter edge portion of the turntable 3.

[0023] At the left and right sides of a front end portion of the cab 10,support posts 14 a, 14 b are provided, and, at a front end part of therear wall surface section of the outer side portion 11, a support post14 c. At a longitudinally intermediate section of the inner side portion13 of the cab 10, a support post 14 d is provided, and, at a rearsection of the support post 14 d, flat glass 15 is fixed. The cab 10 isprovided at a rear portion thereof with outwardly bulgingtwo-dimensionally curved rear glass 16, an outer edge of which isadapted to stay on the inner side of the turning radius R of the outeredge portion of the upper turntable 3. The outer side portion 11 isprovided at the rear wall surface section thereof with two-dimensionallycurved glass 17.

[0024] The radius of curvature Al of the rear curved glass 16 is equalto that A2 of the side curved glass 17. The contact portions of the flatglass 15 and side curved glass 17 and those of the rear curved glass 16are bonded together and sealed with, for example, a silicone agent.

[0025] The cab 10 is provided therein with an operator's seat 40 havinga back 41 capable of being reclined. A clearance L between the back 41and rear curved glass 16 can be set larger than that M in a related artcab since the rear curved glass 16 is bent outward. Therefore, thereclining angle α of the back can be set larger than that β thereof inthe related art cab.

[0026] Since the slide door-carrying cab according to the presentinvention is formed as described above, the following effects aredisplayed. The outwardly bulging rear curved glass 16 is provided on theouter side of the rear portion of the cab 10 so that the glass 16 stayswithin the turning radius of the outer edge portion of the upperturntable 3. Accordingly, there is not a fear of causing the rear curvedglass 16 to contact an outside obstacle during a swinging movement ofthe turntable 3. Since the clearance between the back 41 of theoperator's seat 40 and rear curved glass 16 can be set larger than thatbetween the corresponding parts of the related art cab, a space inwhich, for example, a tool box is placed can be secured sufficiently inthe clearance. Moreover, the angle at which the operator's seat 40 isreclined becomes larger than that at which the operator's seat in therelated art cab is reclined, so that the operator can take a break in acomfortable posture during a rest period. This enables the operator'scomfort in the cab when he works and rests therein to be improved.

[0027] Since support posts are not provided in the left and right rearcorner portions of the cab 10, the rear visual range is widened. Theexternal appearance of the cab is improved since the glass in the rearportion thereof is made curvilinearly. Moreover, when the radius ofcurvature of the rear curved glass 16 and that of the side curved glass17 are set equal to each other, the same-mold can be used in common withthese glass during the manufacturing thereof, and this-enables the costto be reduced.

What is claimed is:
 1. A slide door-carrying cab for a constructionmachine, wherein the cab is provided in a position which is offset fromthe center of a swing movement of a turntable swingably mounted on atraveling gear, the cab comprising: an outer side portion and a rearportion each of which has a curved surface on an outer circumferentialside of the turntable so that each of the curved surfaces bulgesoutward, and a slide door provided in the outer side portion so that theslide door is opened and closed as the slide door is moved slidinglyalong the curved surface of the outer side portion with an outer edge ofan orbit of the opening and closing movements of the slide door stayingwithin a turning radius of an outer edge portion of the turntable,wherein the rear portion is made of rear curved glass staying within theturning radius and having an outwardly bulging curved surface.
 2. Theslide door-carrying cab according to claim 1, wherein the radius ofcurvature of the rear curved glass is set equal to that of the sidecurved glass provided at a rear section of the outer side portion.